Footwear having a preformed closed-loop welt structure

ABSTRACT

A footwear having an outsole coupled to an upper by a preformed closed-loop welt. The welt is a formed ring-shaped structure having no ends or breaks. The welt is sized and shaped to receive the upper-outsole junction. The welt provides an intermediary structure for coupling the outsole to the upper. The welt includes a sidewall that facilitates stitching and gluing an upper portion of the sidewall to the upper.

[0001] This application claims priority to Taiwan Patent Application No. 091,208,706, filed on Jun. 11, 2002, entitled, “Reinforced Welt”, which is incorporated by reference in its entirety.

BACKGROUND OF THE INVENTION

[0002] 1. Field of the Invention

[0003] This invention relates to footwear construction, particularly to durable and rugged footwear construction.

[0004] 2. Description of Related Art

[0005] Footwear worn for outdoor hiking or on rugged surfaces often feature better durability than other types of footwear thanks to their comparatively higher structural and manufacturing standards. The Goodyear Welt Construction is a well-known standard in rugged footwear construction. The Goodyear Welt Construction involves using a welt strip as an intermediary structure for joining an outsole to a shoe upper. FIG. 1 is a side view of portions of a footwear 1 employing the conventional Goodyear Welt Construction, in which the toe section of the footwear 1 is shown in cross-sectional view. The footwear 1 includes a conventional welt strip 2, an upper 5 (having a vamp 7 and a quarter 9), an outsole 12, and a midsole 13. The welt strip 2 provides an intermediary structure for joining the outsole 12 to the upper 5.

[0006]FIG. 2 is a perspective view of the conventional welt 2. The welt 2 is an open-loop strip-like structure made of plastic or leather having two ends 14 and 15. The welt 2 has a substantially L-shaped cross section having a sidewall 16 and a rib 17 extending from the sidewall 16. The sidewall 16 has an upper portion 18 above the topside of the rib 17 and a lower portion 19 below the bottom side of the rib 17. The height “h” of the upper portion 18 is substantially uniform along the length of the welt strip 2. As shown in FIG. 1, the height of the upper portion 18 is short as compared to the height of the vamp 7 or the quarter 9. Furthermore, in this particular welt configuration, the height “h” of the upper portion 18 is shorter than the width “w” of the rib 17. In other words, the surface area of the sidewall 16 is substantially negligible as compared to the surface area of the upper 5. The welt 2 can also include a groove 21 located on the bottom side of the rib 17 at the junction of the lower portion 19 and the rib 17.

[0007] Referring to FIGS. 1 and 2, the welt 2 facilitates the joining of the outsole 12 to the upper 5. In accordance with Goodyear Welt Construction, the welt strip 2 is placed along the junction of the outsole 12 and the upper 5. The welt strip 2 is then coupled to the upper 5 by horizontally machine stitching (i.e., in a direction along the periphery of the upper 5) or stapling the lower portion 19 of the sidewall 16 to the upper 5 and/or the insole 13 along the groove 21. The upper portion 18 is not coupled to the upper 5. The welt strip 2 is also coupled to the outsole 12 by horizontally machine stitching or stapling the rib 17 of the welt strip 2 to the outsole 12. The horizontally machine stitching commences from the end 14 of the welt strip 2 and continues around the periphery of the upper-outsole junction until the end 15 is almost joined with the end 14. FIG. 3 is a bottom perspective view of the footwear 1 showing the ends 14 and 15 of the welt strip 2 almost joined together.

[0008] Because the welt 2 has an open-loop strip shape, the two ends 14 and 15 of the strip must inevitably be joined together, resulting in seam 22. Current Goodyear inseam trimming machines do not allow the welt 2 to be cut and the two ends 14 and 15 to be stitched together smoothly. Consequently, manual operation is required to precut the welt strip 2 to a length slightly longer than the periphery of the upper-outsole junction. FIG. 3 shows the extra length of welt strip 23. The extra length of welt strip 23 is shown by the dotted line. The welt strip 2 is stitched from the end 14 to almost the other end 15. Before the ends 14 and 15 are joined, the extra length 23 of welt strip 2 is manually cut and the remaining unstitched welt strip 2 is stitched. It is critical that the ends 14 and 15 be cut so that the ends 14 and 15 match with each other. FIG. 3 shows the break 22 where the ends 14 and 15 meet. This manual operation has caused some obstacles in the streamline automation of the footwear-making process. Thus, it is desirable to have a footwear construction that lends itself to minimal manual operation in the construction process to allow for a more streamlined automation in the footwear-making process.

[0009] Wearers of rugged footwear also require a certain amount of water proofing in their footwear. Under current Goodyear Welt Construction, the upper portion 18 of the sidewall 16 and the upper 5 are not coupled together. The lower portion 19 of the sidewall 16 is stitched to the upper 5 along groove 21. As the conventional welt strip 2 is sewn along the upper 5, chinks can form between the welt 2 and the upper 5. Any chinks can render the footwear I pervious to water, especially in light of the fact that the chinks can occur near the bottom of the footwear 1 where there is more chance of water contact. The chinks can reduce the footwear's durability and life span. As such, it is desirable to have a footwear construction that minimizes chinks in the footwear.

[0010] Use of the conventional welt strip in footwear construction is disclosed in U.S. Pat. No. 6,226,895, to McClelland, issued on May 8, 2001, entitled Footwear Construction. McClelland describes the welt strip as being conventional (col. 3, lines 38-54) and being manufactured by conventional techniques and apparatus such as extruding the welt from a hard durable rubber material (col. 4, lines 64-66), suggesting a welt having a strip shape. The reference discloses stitching the welt by conventional apparatus and techniques, which suggests use of the conventional process of manually precutting an additional length of welt and then manually sizing the ends of the welt just prior to completion. Use of the conventional welt is also disclosed in co-pending U.S. patent application Ser. No. 09/777,130, by Ho, filed Feb. 5, 2001, entitled Footwear with Fixedly Secured Insole for Structural Support.

SUMMARY OF THE INVENTION

[0011] The present invention is directed to a footwear having a preformed closed-loop welt that lends itself to a footwear-making process that is more streamlined and automated than footwear employing conventional welts. The preformed closed-loop welt of the present invention allows the footwear to be manufactured more durable and water-resistant.

[0012] In one aspect of the present invention, the welt is preformed to a closed-loop structure. Unlike conventional welts that are open loop strip-shaped having ends, the welt of the present invention is a formed welt that has no ends. The welt is formed to a continuous closed-loop shaped structure prior to coupling with the footwear upper and outsole. In some aspects of the present invention, the welt is preformed to the closed-loop shape by coupling the ends of the welt prior to coupling the welt to the footwear upper and outsole. In some aspects of the present invention, the welt is preformed to the closed-loop shape having no seams. In some aspects of the present invention, the welt can be specifically sized and shaped to receive a particular footwear or be universally sized and shaped for any particular footwear.

[0013] In another aspect of the present invention, the closed-loop welt has a tall sidewall and a rib extending from the tall sidewall, such that the height of the sidewall is longer than the width of the rib. The tall sidewall defines a sufficiently large surface area that provides the welt with a larger contact surface for coupling the sidewall to an upper of the footwear. Additionally, the larger surface area allows aesthetic and functional elements to be defined on the welt. In some aspects of the present invention, the sidewall has a variable height that is taller near the toe and heel sections of the welt. In another aspect of the present invention, the closed-loop welt includes an adhesion layer for facilitating coupling the welt to the footwear.

[0014] The present invention is also directed to a method of manufacturing a footwear that is more durable and water-resistant, in which the method lends itself to a more fully automated process. The method includes providing a preformed closed-loop welt, coupling the welt to the upper, and coupling the welt to the outsole. Providing the preformed closed-loop welt permits coupling the welt to the upper and the outsole with conventional stitching means from beginning to end, thus allowing for a continuous automated process. In some aspects of the present invention, coupling the welt to the upper includes bonding the welt to the upper with an adhesive material. The larger surface area of the sidewall provides a larger contact surface for applying the adhesive material between the sidewall and the upper. The bonding step allows the footwear to be manufactured more durable and water-resistant.

BRIEF DESCRIPTIONS OF THE DRAWINGS

[0015] The present invention will be more clearly understood when considered in conjunction with the accompanying drawings. In the following drawings, like reference numerals designate like or similar parts throughout the drawings.

[0016]FIG. 1 is a side view of portions of a footwear employing the conventional Goodyear Welt Construction, wherein the toe section of the footwear is shown in cross-sectional view.

[0017]FIG. 2 is a perspective view of a conventional Goodyear welt. FIG. 3 is a bottom perspective view of the footwear of FIG. 1 showing the ends of the welt strip almost joined together.

[0018]FIG. 4 is a side view of a footwear having a preformed closed-loop welt in accordance with one embodiment of the present invention.

[0019]FIG. 5 is a perspective view of the preformed closed-loop welt in accordance with one embodiment of the present invention.

[0020]FIG. 6 is a side view of the preformed closed-loop welt shown in FIG. 5.

[0021]FIG. 7 is a bottom view of the preformed closed-loop welt shown in FIG. 5.

[0022]FIG. 8 is a side view of the footwear shown in FIG. 4, in which the welt is shown in cross-sectional view.

DESCRIPTION OF PREFERRED EMBODIMENTS

[0023] The present description is the best contemplated mode of carrying out the invention. This description is made for the purpose of illustrating general principles of the invention and should not be taken in a limiting sense.

[0024]FIG. 4 is a side view of a footwear 25 having a preformed closed-loop welt 30 in accordance with one embodiment of the present invention. The footwear 25 includes an upper 60, an outsole 70, and the preformed closed-loop welt 30. The upper 60 includes a vamp 63 and a quarter 66. The upper 60 is sized and shaped to receive a foot of a wearer and to secure the foot of the wearer within the upper 60. The outsole 70 is coupled to the upper 60 at an upper-outsole junction 72. The outsole 70 is adapted to support the weight of the wearer on top and is capable of traction against rough outside contact surfaces on bottom. The outsole 70 can be formed from a substantially wear resistant material, such as high-density carbon rubber.

[0025]FIG. 5 is a top perspective view of the preformed closed-loop welt 30 in accordance with one embodiment of the present invention. The preformed closed-loop welt 30 includes a tall sidewall 32 and a rib 34 extending from the sidewall 32. FIG. 6 is a side view of the preformed closed-loop welt 30 shown in FIG. 5. The sidewall 32 has an upper portion 35 above the rib 34 and a lower portion 46 below the rib 34. The sidewall 32 is tall in that the height “h” of the upper portion 35 is substantially greater than the width “w” of the rib 34 (shown in FIG. 5). Accordingly, the tall sidewall 32 defines a substantially large surface area, which enhances the contact surface the sidewall 32 has with the upper 60.

[0026] Referring to FIG. 's 5 and 6, the height “h” of the upper portion 35 is variable along the periphery of the welt 30. For example, the height of the upper portion 35 at a toe section 36 and a heel section 37 is taller than at a middle section 38. As such, the surface area of the upper portion 35 at the toe and heel sections 36 and 37 are greater than at the middle section 38. The upper portion 35 at the toe and heel section 36 and 37 is sized and shaped such that the welt 30 can include any number of aesthetic and/or functional elements. For example, at the toe section 36, the upper portion 35 can include an anti-friction corrugated surface 39. The added surface area also provides the welt 30 with a larger contact surface with the upper 60 to facilitate the upper portion 35 being coupled to the upper 60 during construction of the footwear 25. In alternative embodiments of the present invention (not shown), the height of the upper portion can be substantially uniform along the periphery of the welt or can be taller at the middle section than at the other sections of the welt.

[0027] In certain embodiments of the present invention, the welt 30 is preformed to the relative shape of the upper 60. For example, the vamp 63 and the quarter 66 portions of the upper 60 have a slight curved or arched profile. As shown in FIG. 6, the toe and heel sections of the welt 36 and 37 are preformed having substantially the same relative curved profile. The formed shape of the sidewall 32 facilitates securely coupling the welt 30 to the upper 60 and minimizes the formation of chinks between the upper 60 and the sidewall 32.

[0028]FIG. 7 is a bottom view of the preformed closed-loop welt 30 shown in FIG. 5. FIGS. 5 and 6 show the rib 34 extending from the sidewall 32. The width “w” of the rib 34 is substantially uniform along the periphery of the welt 30. The rib 34 can be shaped and sized to coextend with the periphery of the outsole 70. As will be discussed below, the rib 34 provides an intermediary structure for coupling the upper 60 to the outsole 70.

[0029] Referring to FIG. 's 5 through 7, the seamless welt 30 can include grooves 40 and 42. The groove 40 is defined in the upper portion 35 of the sidewall 32 and is provided substantially along the toe section 36. Alternatively, this groove can be provided substantially along the whole periphery of the welt (not shown). The groove 40 is adapted to receive a stitching 44 (shown in FIG. 4) for coupling the welt 30, and more specifically the upper portion 35 of the sidewall 32, to the upper 60. The groove 42 is defined at the junction of the lower portion 46 and the rib 34. The groove 42 can be provided substantially along the toe section 36 (as shown in FIG. 7), substantially along the heel section 37, or substantially along the whole periphery of the welt (not shown). The groove 42 is likewise adapted to receive a stitching for coupling the welt 30, and more specifically the lower portion 46, to the upper 60.

[0030] Referring to FIG. 6, the rib 34 extends from the sidewall 32 such that the lower portion 46 of the sidewall 32 extends below the bottom side of the rib 34. The lower portion 46 of the sidewall 32 provides a structure for coupling the welt 30 to the upper 60. The lower portion 46 and the groove 42 (shown in FIG. 7) facilitate stitching the welt 30 to the upper 60.

[0031] As mentioned herein, the conventional Goodyear welt 2 (shown in FIG. 2) is in an open-loop strip having the two ends 14 and 15. In the conventional footwear-making process, the welt strip 2 is machined stitched around the periphery of the footwear 1 until the ends 14 and 15 almost meet. At this point in the process, one end 15 of the welt strip 2 is manually cut to match the other end 14 so that the ends 14 and 15 can be joined. Conventional Goodyear inseam trimming machines do not allow for a smooth cutting and joining of the welt strip ends 14 and 15. The seam or break 22 is formed at the junction where the two ends 14 and 15 of the welt strip 2 meet.

[0032] In contradistinction, the welt 30 of the present invention is in a preformed closed-loop configuration. In other words, the welt 30 is preformed having no seams or breaks and the material of the welt 30 is not joined at a seam to form the ring-shaped structure. The welt 30 is preformed as a continuous loop-shaped structure. As will be described below, the welt 30 has no ends that would require joinder of the ends in the footwear construction process. In some embodiments of the present invention, the welt 30 is preformed by coupling ends of the welt material into the closed-loop shape. The ends of the welt material can be coupled by an adhesive material, a staple, a stitching, or other coupling means allowing for secured coupling of the ends. In some embodiments of the present invention, the welt 30 is preformed having no seams.

[0033] In some embodiments of the present invention, the welt 30 is sized and shaped to receive the periphery of the upper-outsole junction. For instance, the welt 30 can be sized for a specific footwear size. Also, the welt 30 can be universally shaped for either a left or right foot construction (e.g., in a flexible circular ring), or can be specifically shaped for either left or right foot construction. In some embodiments of the present invention, the welt 30 is sized and shaped to snugly fit about the periphery of the upper-outsole junction 72. In other words, the welt 30 is slightly undersized but is capable of being stretched slightly when being stitched.

[0034] The preformed closed-loop welt 30 allows for a more streamlined footwear construction process. In one embodiment of the present invention, a method for constructing a footwear includes providing a preformed closed-loop welt 30, coupling the welt 30 to the upper 60, and coupling the welt 30 to the outsole 70.

[0035] A preformed welt 30 is selected for the particular size and shape of the footwear under construction. The welt 30 can be selected so that the welt 30 snugly fits the periphery of the upper-outsole junction 72. Because the welt material may stretch as the welt 30 is being stitched, selecting the welt 30 so that it is undersized or snugly fitting the upper-outsole junction 72 minimizes the formation of chinks during the stitching process.

[0036] The welt 30 provides an intermediary structure for coupling the upper 60 to the outsole 70. FIG. 8 is a side view of the footwear 25 shown in FIG. 4, in which the welt 30 is shown in cross-sectional view. The welt 30 is coupled to the upper 60 by stitching the sidewall 32 to the upper 60 with treated cotton twine 48 and 50. The sidewall 32 can be stitched along grooves 40 and 42, which are adapted to receive the stitching 48 and 50. The upper portion 35 is stitched to the upper 60 along groove 40. The lower portion 46 is also stitched to the upper 60 along groove 42. By stitching the sidewall 32 at both the upper portion 35 and the lower portion 46, the welt 30 can be more securely coupled to the upper 60, which can result in the footwear 25 being manufactured more durable and rugged. The sidewall 32 being tall facilitates coupling the sidewall 32 to the upper 60 at both the upper portion 35 and the lower portion 46. The welt 30 can be stitched with stitching means well known in the art, such as a Jupiter brand welt-stitching machine. Alternatively, the sidewall 32 can be stapled or nailed to the upper 60.

[0037] In certain embodiments of the method, coupling the welt 30 to the upper 60 can include bonding the welt 30 to the upper 60 with an adhesive material. The welt 30 can include an adhesive material layer 51 (shown in FIG. 5). The adhesive material layer 51 can be an adhesive material well known in the art that allows for sufficient adhesion between the materials of the upper 60 and the welt 30. The adhesive material layer 51 can be preformed on the welt 30 or can be applied just prior to fitting the welt 30 to the upper-outsole junction 72. The adhesive material layer can be provided on the inner side of the sidewall 32 as shown in FIG. 5. The tall sidewall 32 is sized and shaped to define a contact surface with the upper 60 that allows for effective adhesion with the upper 60. The adhesive material can enhance the bond between the welt 30 and the upper 60 to more securely couple the welt 30 to the upper 60, and can minimize the formation of chinks between the sidewall 32 and the upper 60, which can render the footwear 25 less water-resistant.

[0038] The outsole 70 is also coupled to the welt 30. The outsole 70 is coupled to the welt 30 by stitching the rib 34 to the outsole 70 with twine 49. The welt 30 can be stitched substantially along the periphery of the rib 34 or along portions of the periphery of the rib 34. The welt 30 can be stitched with stitching means well known in the art, such as a Jupiter brand welt-stitching machine. Alternatively, the rib 34 can be stapled or nailed to the outsole 70.

[0039] The preformed closed-loop welt 30 of the present invention lends itself to a seemingly streamlined footwear construction process. Because the welt 30 is preformed to the size and shape of the particular footwear 25 under construction, there is no manual welt precutting and sizing steps needed in the footwear-making process. The welt 30 does not have ends that would require any additional manual cutting and sizing in the construction process. The welt 30 can be fitted over the upper-outsole junction 72 and stitched in place. The entire stitching process can be entirely completed by conventional inseam trimming machines. The process of stitching the welt 30 to the upper 60 and to the outsole 70 is substantially uninterrupted, which can result in a more streamlined and automated footwear-making process, which in turn results in reducing the manufacturing time.

[0040] The welt 30 also provides footwear manufacturers with greater latitude in designing the footwear 25 with aesthetic and functional elements on the welt 30. The sidewall 32 of the welt 30 is sized and shaped such that the sidewall 32 allows for a wider range of aesthetic and functional elements to be defined on the welt 30. FIG. 4 shows elements 36 and 37 defined on the sidewall 32. Elements 36 and 37 can be an aesthetic and/or functional element such as an anti-friction corrugated surface.

[0041] While the invention has been described in detail with respect to the illustrated embodiments in accordance therewith, it will be apparent to those skilled in the art that various changes, modifications, substitutions, alterations and improvement may be made without departing from the scope and spirit of the invention as defined by the appended claims. 

What is claimed is:
 1. A footwear comprising: an upper; an outsole coupled to the upper; and a preformed closed-loop welt coupling the upper and the outsole.
 2. The footwear of claim 1, wherein the closed-loop welt is preformed by coupling the ends of a welt material to form a loop configuration prior to coupling with the upper and the outsole.
 3. The footwear of claim 1, wherein the closed-loop welt is seamless.
 4. The footwear of claim 1, wherein the closed-loop welt comprises a tall sidewall and a rib extending from the tall sidewall, wherein the tall sidewall has a height substantially greater than a width of the rib.
 5. The footwear of claim 4, wherein the height of the sidewall is substantially variable along the periphery of the sidewall.
 6. The footwear of claim 5, wherein the sidewall includes an upper portion above the rib and a lower portion below the rib, wherein the height of the upper portion is substantially variable along the periphery of the upper portion.
 7. The footwear of claim 6, wherein the height of the sidewall is substantially taller at a toe section of the welt than at a middle section of the welt.
 8. The footwear of claim 6, wherein the height of the sidewall is substantially taller at a heel section of the welt than at a middle section of the welt.
 9. The footwear of claim 4, wherein the sidewall is shaped to substantially conform to the shape of the upper.
 10. The footwear of claim 4, wherein the height of the sidewall is substantially uniform along the periphery of the welt.
 11. The footwear of claim 4, wherein the closed-loop welt includes an aesthetic element defined on an outer surface of the sidewall.
 12. The footwear of claim 4, wherein the closed-loop welt includes a functional element defined on an outer surface of the sidewall.
 13. The footwear of claim 4, wherein the closed-loop welt includes a groove defined on an outer surface of the sidewall, wherein the groove is adapted to receive a stitching.
 14. The footwear of claim 13, wherein the groove is defined on an upper portion of the sidewall.
 15. The footwear of claim 4, wherein the closed-loop welt is sized and shaped to substantially snugly receive the upper and the outsole at an upper-outsole junction.
 16. The footwear of claim 15, wherein the closed-loop welt is sized and shaped to substantially specifically receive the upper-outsole junction of either a right or left footwear.
 17. The footwear of claim 15, wherein the welt is sized and shaped to substantially universally receive the upper-outsole junction of both a right or left footwear.
 18. The footwear of claim 4, wherein the closed-loop welt includes an adhesive material layer for securely coupling the sidewall to the upper.
 19. The footwear of claim 4, wherein the sidewall is coupled to the upper by a stitching.
 20. The footwear of claim 19, wherein the sidewall is coupled to the upper at an upper portion of the sidewall, wherein the upper portion is sized and shaped to define a surface area with the upper to facilitate coupling the upper portion with the upper.
 21. The footwear of claim 20, wherein the upper portion includes a groove adapted to receive the stitching, wherein the upper portion is stitched to the upper along the groove.
 22. A preformed closed-loop welt for coupling a shoe upper to a shoe outsole, the welt comprising: a tall sidewall; and a rib extending from the tall sidewall; wherein the tall sidewall has a height substantially greater than a width of the rib.
 23. The welt of claim 22, wherein the welt is preformed by coupling the ends of a welt material to form a loop configuration prior to coupling with the upper and the outsole.
 24. The welt of claim 22, wherein the height of the sidewall is substantially variable along the periphery of the sidewall.
 25. The welt of claim 22, further comprising an adhesive material layer on an inner surface of the sidewall.
 26. A method of constructing a footwear having an upper and an outsole coupled to the upper, the method comprising: providing a preformed closed-loop welt having a tall sidewall and a rib extending from the tall sidewall; coupling the welt to the upper; and coupling the welt to the outsole.
 27. The method of claim 26, wherein coupling the welt to the upper includes gluing the sidewall to the upper.
 28. The method of claim 27, wherein gluing the sidewall to the upper includes gluing an upper portion of the sidewall to the upper. 